Add 10.0.2.2 as alias for the loopback interface upon startup.

ipalias.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>ipalias</string>
    <key>ProgramArguments</key>
    <array>
        <string>ifconfig</string>
        <string>lo0</string>
        <string>alias</string>
        <string>10.0.2.2</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
</dict>
</plist>